Some mead makers will add a dozen ingredients in their meads (fruits, species, etc.) but fewer seem to blend honeys. It is a great way of improving the complexity and the balance of a mead though. This is commonly done with wines where several kinds of grapes are used (e.g. cabernet sauvignon and merlot for red Bordeaux; pinot noir, pinot meunier and chardonnay in Champagne.) This allows to balance flavor (and cost.)
Some honeys have a very strong flavor which can be overpowering or boring: buckwheat, orange blossom. Orange blossom mead has a great flavor but is very one-dimensional. Buckwheat mead is very strong and buckwheat is likely to kill any other flavor. It can therefore be a good idea to try to blend those with more neutral (and cheaper) honeys such as clover or wild flower.
Another purpose of blending is to match up flavors. As you can use several fruits in melomels or use fruits and spices to get the right taste, you can blend honeys that have noticeably different flavors: orange blossom, buckwheat, tupelo, berries, etc. I currently have 8 batches fermenting, each with a different varietal honey; I plan on blending them within a few months and see what I like.
Why add fruits and spices when there is such a variety of flavors in honeys themselves?
Another use of blending is when one batch is problematic (too dry, fruit or spice taste too strong, honey too strong, too much acid added, etc.) But waste is waste: adding a little vinegar to a fine mead just gives a lot of vinegar. Keep in mind that some problems can be solved by blending and some others cannot. In any case blend and taste small quantities (do not do this alone to get several points of view) before blending larger quantities (about a gallon) and ageing for a few months to see how the batches interact.
← Filling the bottles: there is too much air space in the left bottle [F3]
It is not mandatory... But if one does want to bottle, do as for rackings, siphoning mead from the carboy to the bottles. Leave only half a centimeter of air space between the mead and the cork to reduce oxidation.
Cork the bottles using a new cork. It is possible to recycle used bottles if care is taken to sanitize them properly (after any solid matter is removed, proceed as for carboys). Brown glass is more protective but does not look that great. Recycling green glass wine bottles seems to be a good compromise.
Nowadays, plastic can be used instead of cork. These "plastic cork" seem to be less elastic and therefore harder to use. In a comparison, V9 found that some plastic ones have much poorer results than cork or beer caps. But they are new, so they can be expected to improve quickly and perhaps V9's comments are already out-of-date.
References: chapters 7 in V9 and 17 in V2.
A half dozen years should suffice. To do this, a lot of mead (really a lot) must be made, so that it is impossible to drink everything when it is still young. So a part of the mead made can age.
Bottles are stored horizontally (to prevent the cork from drying) in a room with an average humidity: too dry and the corks dry and leak, too humid and bacteria can grow. If wine bottles and corks are not used (this can be done is mead is not to be aged and will be drunk soon), it is not always necessary to take some much care of humidity or to keep bottles horizontal, this can even be to be avoided is the (metallic, rubber, etc) stopper can harm the taste of the mead. Bottles are aleways stored in a dark room at a steady temperature between 10 and 15°C (50 and 60°F).